干旱区生态环境知识资源中心

In cooperatively breeding and other family living species, there are often more individuals of reproductive age than available breeding positions. Asking how individuals attain reproductive status is therefore crucial if we are to understand the selection pressures that operate in these groups. Here, we present data on routes to breeding in pied babblers Turdoides bicolor, cooperatively breeding passerines from the Kalahari Desert. Individuals of both sexes remained on the natal territory into adulthood, despite being relatively unlikely to breed there. Instead, individuals seemed to use the natal territory as a base to monitor the availability of breeding positions elsewhere. Both sexes were most likely to attain breeding status by moving into vacant breeding positions on non-natal territories, although females also occasionally seized breeding positions by overthrowing breeding females on foreign territories. We discuss these patterns in the context of existing theoretical and empirical data.